Controlled spalling technology can be employed to remove thin substrate (e.g. silicon) film from a relatively thick substrate, enabling a wide range of applications including low cost solar cells and thin film flexible electronic devices and structures. The metal stressor layer used in spalling procedures also acts as a supporting layer to assist with handling of the spalled thin film, making thin semiconductor film handling much easier and more reliable. It is necessary, however, to remove the metal stressor layer in some applications, for example to obtain free standing semiconductor thin film to be compatible with high temperature device processing or to expose the original semiconductor substrate surface which is in contact with the metal stressor layer after spalling. Attempts have been made to remove the metal stressor layer using wet and/or dry chemical etching. Non-uniformity in etch rate while employing wet chemical etching through a thick nickel stressor layer may induce cracks in the spalled film. Additionally, complete removal of the thick nickel layer using wet/dry etching may be time consuming, lowering throughput.